First of all, great job and I totally look forward to an online and mobile tool for D&D. THANK YOU. 

Quick Profile: I'm a newbie DM based. I played a couple of times before using pre-WOTCand 3.5. rules. I only started running my own campaigns during D&D Next. About to start a 5e campaign using the Planeshift-Innistrad setting (another notable move, by the way).

PHASE 1 Feedback: 

a. Compendium 

• Would appreciate the rules on building characters (race, class, background, etc.)
• Referencing the section (or pages) from the sourcebooks will be helpful
• Re-arrange the sections so that you can divide the rules between those targeting players and DMs
• I see that you include the Planes of Existence, you might as well include Deities (these can be paid content)
• Adding more photos should liven up the whole Compendium section
• A step-by-step character generation guide should stand out for new players (with hyperlinks to the detailed sections/rules)
  1. Choose a Race
  2. Choose a Class
  3. Determine Ability Scores
  4. Describe your Character
  5. Choose Equipment
  6. Choose Spells (if applicable)

b. Spells

• What's V, S, M? Can this be spelled out for people new to D&D? 
• Referencing the section (or pages) from the sourcebooks will be helpful
• Photos of the spell would also help players imagine the effect 
• A quick reference on spell slots

c. Items

• Referencing the section (or pages) from the sourcebooks will be helpful
• Photos of the item would also help players imagine the effect 
• Missing info are pre-requisites, range, damage, weight, gp value
• How about a random magic item generator? 

d. Monsters

• Good job on the Photos (I hope you are going to the do same with Items and Spells) 
• Also, good job the monster info, consistent with the sourcebooks
• How about including speed as a filter category? 

e. Others

• Forum looks clean and easy to use
• Account preferences --- perhaps you can add Player, DM, or both option; another is to include if the user is open for invitations
• Official and pre-made Avatars for users? 
• I like the "leveling up" concept, maybe add a few more flavor and content (like achievements, etc.) but low priority
• Linkage to DCI number? 

WISHLIST

• Downloadable content (free or purchased) such as maps, printed character sheets + image, adventures
• Mobile-friendly version for actual gaming purposes 
• Character management should include stats, background, feats, gear, spells, encumbrance, treasure, etc. 
• Character development with several images to choose from 
• DM-only content such as campaign management, maps, NPC generator
• Interactive map --- well, the ability to hide or reveal a section of a map
• Dice tool? 
• Photos of monsters, spells and items --- full screen option, so DMs can show it on screen
• Subscription options
  • Free --- access to rules, compendium, 1 unlinkable character sheet
  • Regular --- up to 3 character profiles that are linkable to campaigns 
  • Advanced --- access to premium content and all your other goodies

Again, thanks for this wonderful and ambitious product. I look forward to Phase 2 of your Beta.